I've posted a couple times about this, and submitted it to the wish list.
http://kisslicer.com/forum/index.php?topic=163.msg6921#msg6921Take a look at the time differences!
Was in Official Beta release, but changed in Official release.
Beta incrementally steps down feedrate from infill speed to perimeter speed in accordance with the number of loops.
I still use Beta for this feature to speed up my print times, but a lot of what I print really needs jitter, which Beta doesn't do.
I get my best surface quality at 10mm/s or slower, but my machine can run up to 50mm/s.
There is a back-pressure build up in the hot end when dropping speed directly from fast to slow, resulting in overflow at the start of the perimeter loop. Releases after Official Beta print all loops except the perimeter at full infill speed.
I would personally prefer step-down, but would take separate loop speed.